Typewriting machine



Nov. 28, 1933. R. G. THOMPSON TYPEWRITING MACHINE Filed April 30, 1930 3Sheets-Sheet l I Wall/11111111111 Nov. 28, 1933. R G TH P N 1,937,047

TYPEWRITING MACHINE Filed April 50, 1950 I 3 Sheets-Sheet 2 I I C I///////I///////// I l I & If I 64 .INVENTOR 721's ATTORNEY Nov. 28,1933.

R. e. THOMPSON TYPEWRITING MACHINE Filed April 30, 1930 5 Sheets-Sheet 3mvau ma RgsseZGT/l Q Zia ATTORNEY Patented Nov. 28 1933 TYPEWRITINGMACHINE Russell G. Thompson, Rochester, N. Y., assignor to ElectromaticTypewriters,. Inc., Rochester,

N. Y., a corporation of New York Application April 30, 1930. Serial No.448,564

2 Claims.

This invention relates to typewriting machines, and particularly topower driven means for operating the type action of such machines.

The principal object of .this invention is to provide power means formoving the type bars into engagement with the platen in a typewritingmachine of the so-called noiseless type, in which the type bars arearranged radially with respect to the printing point and move insubstantially straight lines to and from said printing point.

Another object of the invention is to provide power means for moving thetype bars into engagement with the platen, said type bars being carriedon swinging arms or, supports, whereby they move bodily to and from theplaten in substantially straight lines.

Still another object of the invention is to provide power means fortilting a type bar of this kind having a plurality of printingcharacters to aline a selected character with the printing point on theplaten.

A still further object of the invention is to provide power means formoving the type bars to the printing position in a typewriting machineof the noiseless type and having a plurality of type thereon arranged ingroups, a key lever associated with each of said groups, at least one ofwhich key levers controls means for tilting the type bar to print from aselected group of type, interlocking means being provided between saidkey levers for preventing the actuation of one of said keylevers whenanother is actuated.

Still another object of the invention is to provide means in a bodilymovable type bar for 35 impressing 'the upper case type on the work withgreater force than the lower case type.

To these and other ends, the invention consists in the construction andarrangement'of parts that will appear from the following descriptionwhen read in conjunction with the accompanying drawings, the novelfeatures being pointed out in the claims following the specification.

In the drawings:

Fig. 1 is a transverse section of a typewriting machine illustrating oneembodiment of the invention, parts being brokenaway and others shown insection;

Fig. 2 is a similar view showing the type bar in position to print fromits lower group of type;

Fig. 3 is a similar view showing the type bar in position to print fromits upper group of type;

Fig. 4 is a fragmentary view showing means for rendering the type bartilting means inoperative;

Fig. 5 is a fragmentary front elevation of the key lever guide, showingthe interlocking means between key levers, and

Figure 6 is a fragmentary view similar'to Fig. 4 showing parts inanother position.

Referring particularly to the drawings, in which like reference numeralsrefer to the same parts in all the figures, there is illustrated atypewriting machine of well known noiseless type, in which the type bars1 are arranged radially about the printing point on the platen 2 andmove bodily in substantially straight or slightly curved paths to andfrom the printing point to engage the platen or a work sheet thereon.Each of the type bars carries four types arranged in vertical alinementin groups 3 and 4 of two types each, corresponding to upper and lowercase, each type bar being operable by either one of two keys 5 and 6,associated therewith and corresponding in number to the number of groupsof characters on the type bar or the number of characters in each group,one of which is adapted to set in operation instrumentalities fortilting the type bar to select the particular group to be printed, whilethe platen is shiftable in the usual manner to bring its printing pointinto the path of the particular type selected to be printed. The platen2 is rotatably mounted in a carriage adapted to move transversely on theframe 7 for letter and word spacing, as usual in this art.

Each of the type bars is carried on supports comprising links 8 and 9pivoted to the bar, the link 8 being pivoted at 10 adjacent its rear endor head. The link 8 is mounted to swing on a pivot 11 carried on aswinging member or lever 12, while the link 9 turns on a pivot 13mounted in a bracket fixed to the frame of the machine. The swingingmember 12 is in the form of abell crank lever carried on a fixed arm 14mounted on the frame of the machine for limited adjustment thereon. Whenthe type is actuated to move to the printing point from the Fig. 1 tothe Fig. 2 position, it moves bodily in a slightly curved path on thepivoted links 8 and 9 and is held against lateral thrust by the guidingmember 15 in which it moves.

The path in which the type bar moves is slightly curved or has a longradius of curvature, and due to the changed position of the link 8relative to the link 9 when printing from the upper group oftype, thecurve of the path is reversed, although of the same general character.In order to swing the bell crank 12 to the Fig. 3 position to print fromthe upper group of types, the bell crank is pivotally connected at 19with a link 18 pivotally connected with an actuator 20 1'! the form of abell crank lever pivoted at 21 to a bracket on the frame of the machine.A fixed stop 20 on the reverse side limits the movement of the actuatorin both directions, see Figs. 4 and 6.

The arrangement of the lever 20 and link 18 is such as to form a togglenormally held in the straight line position of Figs. 1 and 2 by theengagement of the lever 20 with its fixed stop, when printing from thelower group of characters on the type bar. The forward end of the lever20 has an actuating link 23 pivoted thereto, whereby it may be moved tothe other extreme limit of its movement to move the parts of the toggleto the Fig. 3 position and swing the link 8 and the rear end of the typebar downwardly to print from its upper group of type. The link 23 may beactuated by a key lever, but in the present instance power driven meansare provided for actuating it.

Pivoted on the stud 21 concentric with the lever 20 is a second bellcrank lever or actuator 24 which is also power operated through the link25'pivoted thereto. A link 26 is pivoted to the actuator 24 and connectsit with one arm of a lever 27 pivotally mounted on a fixed bracket 28.The other arm of said lever is ofiset and extends to the opposite sideof its support where it is provided with an arm 27' adapted to engagethe actuator 20 and prevent actuation thereof when the link 25 isoperated to print from the lower group of type, see Fig. 4.

A main driving lever 30 is pivoted at 31 on a fixed bracket. Saiddriving lever is a bell crank in type and constructed of two identicalparts spaced from each other, and each having a rearwardly anddownwardly curved arm 32, said arms being connected by a plate 32'underlying the forward ends of the actuators 20 and 24. The forward ends33 and 34 of said actuators are similar in shape, each having a curvedportion adapted to contact the arm 32 and swing the main driving leveron its pivot when one or the other of the actuators 20 or 24 is actuatedby one of the links 23' or 25. At its upper end the lever 30 isconnected by means of a link 36 with a bell crank lever 37 pivoted atone end on a fixed bracket and pivotally connected at its other end withthe forward end of a link 38 pivotally connected at its rear end withthe type bar 1. The lever 37 and link 38 constitute in effect a toggleso that when the lever 30 is operated by one or the other of itsactuators from the Fig. 1 to the Fig. 2 or Fig. 3 position, they move tothe substantially straight line position shown in the latter views, theparts being so adjusted that the toggle straightens with consequentslowing up of its motion just as the type bar contacts with the surfaceof the platen.

In order to provide means for fully straighten ing the toggle to pressthe type into contact with the platen, a weight 40 is'provided on theend of the link 36 which is normally arranged in front of the lever 30,as seen in Fig. 1, but swings forwardly over the lever 30 with the typebar to the Fig.2 position and gains momentum to move the parts of thetoggle to the straight position shown in said Fig. 2. In order to insurecomplete return movement of the parts to the Fig. 1 position and preventrebound, a link 41 is loosely pivoted to the weight 40 at one end and toa link 42 at its other end. The link 42 is pivoted to a fixed part andwith the link 41 constitutes a toggle normally in the straight positionshown in Fig. 1. When, however, the type bar is actuated to print, theparts of the toggle assume the position shown in Fig. 2 and serve toabsorbv the momentum of the weight on the return movement. The link 41is provided with a stop arm 43 adapted to engage a stop 44 on the weightto prevent rebound on the return stroke. This toggle formed by the links41 and 42 serves to absorb the momentum of the parts on the returnmovement and causes them to come to rest in a noiseless manner.

Pivoted to the lower part of the lever 30 is link 45 bifurcated at itslower end to straddle and engage a universal bar 46 for operating theescapement or other devices, as usual in the art. The lever 30 is alsoprovided with an integral arm 47 projecting forwardly therefrom andadapted to engage a fixed stop 48 to limit its turning movement. Thestop 48 may be provided with a resilient pad 48' of felt or soft rubberto render the engagement therewith of the arm 47 substantial lynoiseless. A second stop 40 is arranged on the frame member 7 in thepath of the weight 40. The stop 40 is also constructed of soft resilientmaterial. By this arrangement, it will be noted that the stop 48' is anoiseless stop for limiting the movement of the toggle 37, 38 and thetype bar and parts movable therewith in one direction, and the stop 40'is a noiseless stop for limiting the movement of said parts in the otherdirection.

The essential features ofthe parts thus far described are substantiallythose of a well known noiseless typewriting machine and form no part ofthe present invention except as they enter into combination therewith.

According to the present invention, power driven means are provided foractuating one or another of the links 23 or 25 selected by the actuationof one or another of the corresponding key levers 5 or 6. To this end,the links 23 and 25 are respectively pivotally connected with actuators50 and 51, mounted in the base of the machine. The actuators 50 and 51are similar in construction except that they are arranged to extend inopposite directions from the lower ends of the links. It is thereforebelieved that a de tailed description of one will suffice.

The actuator 51 is in the form of a bell crank lever pivoted at' 53 tothe frame of the machine. It has an arm 54 extending rearwardly from itspivot, to the rear end of which the link 25 is pivoted at 55. It alsohas another arm 56 extending downwardly from the pivot 53, on the lowerend of which a cam 57 is rotatably mounted at 58, which cam normallylies closely adjacent the surface of the driven roller 59 but is adaptedto move into frictional engagement therewith to posed lugs 64, one orthe other of which is normally engaged by a stop lever 65 having alateral projection 66 on one of its arms adapted to engage one or theother of the lugs-64 to stop the 1 cam and retain it against actuationby the spring fingers The other arm of the stop lever has a laterallyprojecting lug 67 adapted to be engaged ,by the forked end 68 of one ofthe key levers,

case type against the platen. when, however, the platen is moved orshifted relatively to the type bars, the upper case type is impressed onthe platen or the work sheet thereon. The forward movement of the typebar is substantially uniform at each actuation, due to the action of thetoggle by which it is actuated. By an inspection of Fig. 1, it will benoted that the upper case type 3" of each group is raised from the faceof the type bar to a greater extent than the lower case type 3 so thatwhen the toggle which actuates the type bar is straightened, the uppercase type projects beyond the plane of the lower case type to engage theplaten or the work sheet thereon with greater pressure when the toggleisstraightened, By this construction, the .upper case types may beimpressed on the work sheet with the same weight per unit of area as thelower case types, although of comparatively greater area.

The operation briefly stated is as follows: The parts are normally inposition to print from the lower group of type on the type bar. When thekey lever 5 is depressed, as shown in Fig. 2, the

stop lever 65 connected therewith ismoved fromengagement with its lug 64on the cam 57, thus permitting the cam to rotate under the action of itsspring finger 62 into engagement with the driven roller 59, which isfrictionally engaged thereby. The cam is then rotated by the roller andturns the actuator on its pivot and depresses the link 25 connectedtherewith, thus swinging the actuator 24 to lock the other actuator 20and swing the .lever 30 to move the type bar to the printing point.

' When the other key lever 6, also adapted to actuate the type bar 1, isdepressed, as shown in Fig. 3 to print from the upper group of type, thecompanion actuator 50 is operated in substantially the same manner asthe actuator 51 to depress the link 23 and move the actuator 20 whichswings the lever 12 and through it the supporting lever 8 to move therear end of the type bar downwardly to bring its upper group of type tothe printing point. During such movement the type bar swings on the link9. Said actuator 20 also engages and swings the lever 30 to move thetype bar to the printing position.

When the type action is operated rapidly by power. there is a tendencyof the parts to drag and rebound. It has been found that this can beeflectively overcome by resiliently connecting the arm 32 of the lever30 with the actuators 20 and 24 by means of retraction springs such as73. which resiliently retain the lever 30 in its normal position.

It will be noted that two key levers 5 and 6 are associated with each ofthe type bars 1. In practice, it has been found that there is liabilityof an operator striking two keys associated with the same type bar atthe same time. Should this occur, it would be likely to result inserious injury to the parts. To overcome this liability, means have beenprovided for engaging one of the key levers and preventing its actuationwhen the other is operated, thus preventing the simultaneous actuationof both key levers associated with the same type bar.

Referring to Fig. 5 of the drawings, it will be noted that the keylevers engage verticallyarranged slots 75 in a fixed member or comb '76,which serves to guide their movements to vertical planes. The key levers5 and 6 associated with any one of the type bars 1 are arranged inadjacent slots '75, and pivoted on the rear face of the comb 76 midwaybetween the adjacent slots are locking members '77 which projectlaterally from their pivots beneath the adjacent key levers which areassociated with one of the type bars and over the slots in the comb inwhich said key levers are guided. The locking members 7'7 are pivotedintermediate their ends so that they normally occupy a horizontalposition under the action of gravity; When one or the other of the keylevers 5 or 6 is actuated, it engagesone end of the locking member andswings it on its pivot out of the path of the key lever, and when thekey lever is released and returns to normal position, the locking memberalso swings back to its normal position under the action of gravity. Ifboth key levers are struck simultaneously, neither can be actuated adistance suificient to actuate the type bar, since both key leverssimultaneously engage the locking member on opposite sides of its pivotand each key lever prevents it from swinging out of the path of theother.

Although only one embodiment of the invention is shown and describedherein, it will be understood that this application is intended to coversuch changes or modifications as come within the spirit of the inventionor scope of the following claims.

I claim:

1. A type action for typewriting machines, comprising a bodily movabletype bar, a plurality of groups of type thereon, key levers associatedwith said type bar and corresponding in number to the number of groupsof type, an actuator operatively connected with each of said key levers,a bell crank lever operatively connected with the type bar for moving itto the printing point and having a part arranged in the path of saidactuators, power operated means controlled by the depression of any ofsaid key levers for moving the type bar to the printing point, andresilient means connecting said bell crank lever to. the actuators.

2. A type action for typewriting machines, comprising a bodily movabletype bar, a plurality of 125 groups of type thereon, key leversassociated with said type bar and corresponding in number to the numberof groups of type, movable means on which said type bar is supported, anactuator operatively connected with one of said key levers 130 and withsaid movable means for tilting the type bar, a second actuatoroperatively connected with another of said key levers, a bell cranklever operatively connected with the type bar for moving it to theprinting point and having a part arranged in the path of said actuators,power operated means controlled by the depression of any of said keylevers for moving the type bar to the printing point, and resilientconnections between said

